Regulation of human oocyte maturation in vivo during the final maturation of follicles.

Study Question: Which substances and signal transduction pathways are potentially active downstream to the effect of FSH and LH in the regulation of human oocyte maturation in vivo?

Summary Answer: The regulation of human oocyte maturation appears to be a multifactorial process in which several different signal transduction pathways are active.

What Is Known Already: Many studies in animal species have provided insight into the mechanisms that govern the final maturation of oocytes. Currently, these studies have identified several different mechanisms downstream to the effects of FSH and LH.

Oocyte diameter predicts the maturation rate of human immature oocytes collected ex vivo.

Purpose: To study the impact of oocyte diameter and cumulus cell mass on the potential for final maturation of immature human oocytes in vitro.

Methods: Immature oocytes (n = 1563) from 75 women undergoing fertility preservation by ovarian tissue cryopreservation (14-41 years) were collected. After preparation of the ovarian cortex for freezing, immature oocytes were collected from the surplus medulla.

The First Dipeptide Mimetic of Neurotrofin-3: Design and Pharmacological Properties.

The dimeric dipeptide mimetic hexamethylenediamide bis-(N-monosuccinyl-L-asparaginyl-L-asparagine) (GTS-301) was created on the basis of the structure of the exposed region of the neurotrophin-3 4th loop. The new compound, as well as the full-length neurotrophin, activated the TrkC and TrkB receptors. GTS-301 showed neuroprotective activity in experiments on HT-22 mouse hippocampal cells under conditions of oxidative stress and glutamate toxicity at concentrations of 10 and 10 M, respectively, and antidepressant-like activity in the forced swimming test on mice with 7-day intraperitoneal administration in doses of 10-40 mg/kg.

Validating Reference Gene Expression Stability in Human Ovarian Follicles, Oocytes, Cumulus Cells, Ovarian Medulla, and Ovarian Cortex Tissue.

Human ovarian cells are phenotypically very different and are often only available in limited amounts. Despite the fact that reference gene (RG) expression stability has been validated in oocytes and other ovarian cells from several animal species, the suitability of a single universal RG in the different human ovarian cells and tissues has not been determined. The present study aimed to validate the expression stability of five of the most used RGs in human oocytes, cumulus cells, preantral follicles, ovarian medulla, and ovarian cortex tissue.

Human Oocyte Morphology and Outcomes of Infertility Treatment: a Systematic Review.

Oocyte morphology assessment is easy to implement in any laboratory with possible quality grading prior to fertilization. At present, comprehensive oocyte morphology scoring is not performed as a routine procedure. However, it may augment chances for successful treatment outcomes if a correlation with certain dysmorphisms can be proven.

Histidine buffered media maintains pH stabile during cooled transportation of human ovarian tissue.

The aim of this study was to investigate whether pH is stable when transporting ovarian tissue in media buffered with either HEPES or histidine. Furthermore, if the choice of transport media impacts the in vitro maturation rate of oocytes collected in connection with ovarian tissue cryopreservation. Human ovaries (n = 34) collected for ovarian tissue cryopreservation were transported immersed in either 30 ml of HEPES buffered (follicle flushing media (Origio; Denmark)) or histidine buffered media (Custodiol®-HTK, Koehler-Chemie, Germany).

Use of cryopreserved ovarian tissue in the Danish fertility preservation cohort.

Objective: To evaluate the use of cryopreserved ovarian tissue in the Danish fertility preservation cohort.

Design: Retrospective cohort study.

Setting: University hospitals and fertility clinics.

A threshold concentration of FSH is needed during IVM of ex vivo collected human oocytes.

Purpose: To investigate the effect of different FSH concentrations on human oocyte maturation in vitro and its impact on gene expression of key factors in the surrounding cumulus cells.

Methods: The study included 32 patients who underwent unilateral oophorectomy for ovarian tissue cryopreservation (OTC) (aged 28 years on average). Immature oocytes were collected from surplus medulla tissue.

Neuroregenerative Activity of the Dipeptide Mimetic of Brain-derived Neurotrophic Factor GSB-106 Under Experimental Ischemic Stroke.

Background: A dimeric dipeptide mimetic of the BDNF loop 4, bis(N-monosuccinyl- L-seryl-L-lysine) hexamethylenediamide (GSB-106) activates TrkB, PI3K/AKT, MAPK/ ERK, and PLC-γ1, and was created at the V.V. Zakusov Research Institute of Pharmacology.

Clusters of smooth endoplasmic reticulum are absent in oocytes from unstimulated women.

Research Question: What is the frequency of morphological dysmorphisms in immature human oocytes collected ex vivo from small antral follicles and matured in vitro?

Design: Human ovaries (n = 56) were excised for ovarian tissue cryopreservation (OTC). None of the patients had received exogenous gonadotrophins prior to the procedure. Immature oocytes released from small antral follicles were collected in connection with isolation of the cortex for OTC.

Improving the maturation rate of human oocytes collected ex vivo during the cryopreservation of ovarian tissue.

Purpose: The aim of the present study was to improve the in vitro maturation (IVM) procedure using oocytes from surplus ovarian tissue after fertility preservation.

Methods: Twenty-five patients aged 17-37 years were included in the study. Maturation was compared between oocytes collected in HEPES-buffered medium or saline, and we determined whether transport on ice prior to oocyte collection affected maturation.

Effects of fast back-fusion of charge transfer excimers on magneto-photocurrent in organic light emitting diodes.

We report the magnetic field dependence of the magneto-photocurrent (MPC) in organic light emitting diodes made of homo-polymer organic layers and compare it to the measured magneto-conductance (MC) in the same diodes. We find that the response MPC(B) is very different from MC(B) in at least two respects. (a) The low field (B < 50 mT) response of MPC(B) is narrower by a factor of ∼5 from that of MC(B).

Chromosome errors in human eggs shape natural fertility over reproductive life span.

Chromosome errors, or aneuploidy, affect an exceptionally high number of human conceptions, causing pregnancy loss and congenital disorders. Here, we have followed chromosome segregation in human oocytes from females aged 9 to 43 years and report that aneuploidy follows a U-curve. Specific segregation error types show different age dependencies, providing a quantitative explanation for the U-curve.

Initial steps in reconstruction of the human ovary: survival of pre-antral stage follicles in a decellularized human ovarian scaffold.

Study Question: Can a reconstructed ovary using decellularized human ovarian tissue (DCT) support survival of pre-antral stage follicles?

Summary Answer: We have demonstrated an effective protocol for decellularization of human ovarian tissues and successful recellularization with isolated human ovarian cells and pre-antral follicles.

What Is Known Already: Survivors of leukemia or ovarian cancer run a risk of reintroducing malignancy when cryopreserved ovarian tissue is transplanted to restore fertility. A reconstructed ovary free of malignant cells could provide a safe alternative.

Innovative multi-protectoral approach increases survival rate after vitrification of ovarian tissue and isolated follicles with improved results in comparison with conventional method.

Background: In recent years, autotransplantation of cryopreserved ovarian tissue became a promising approach to preserve female fertility. The slow freezing is the most effective technique which resulted in greater live birth incidence so far. Despite that, interest to vitrification of the ovarian tissue is swiftly growing, thereby undermining the necessity for further improvements in the technique.

Professional reliability of military pilots: medical and social-psychological aspects.

Presented based on previously performed by the authors the following analysis of the medical, social and psychological aspects of the pilot professional reliability. The scheme of interaction of its structural and functional components is developed, set their coefficients of importance. It is shown that to conform with the requirements of the profession of flight cooperation, social and psychological components of professional reliability of pilots need a set of measures on formation of their professionally important qualities.

[Experience of extracorporeal membrane oxygenation in critical care of respiratory failure in newborn with congenital diaphragmatic hernia in perinatal center].

The article deals with an experience of veno-arterial extracorporeal membrane oxygenation use in preterm infants with congenital diaphragmatic hernia during postoperative period in the perinatal center.

[The social hygienic assessment of pathological affectedness of population].

The article considers the indicator of pathological affectedness to assess population health. This technique enables to forecast beforehand the occurrence of problematic situations in population health and development of diseases. The main elements of social hygienic evaluation of pathological affectedness of population including the results of mass diagnostics of population pathology on the basis of objective (macro-diagnostic, micro-diagnostic and functional analysis) and subjective (counseling, health self-assessment) assessments and the results of autopsy of the deceased from bureau of forensic medical examination and departments of morbid anatomy of large-size hospitals.

[Analysis of life quality of medical emergency rescue service].

The authors evaluated life quality of doctors and paramedics in emergency rescue service. Finding is lower life quality of this occupational category in comparison with inpatient medical personnel. The most unfavorable parameters were seen among nurses, females and individuals aged 41-50.